This is a bit of a "Apples to Toboggans" comparison.
Your first date picker with individual year, month/day/year selections is functional and will let you pick any potential date. (We can't tell from the screenshot but I'm going to presume you can't pick Feb 31st... e.g. there's some logic to filter the options to ensure validity)
In a typical scenario you would click 3 times to "open" each dropdown, scroll if needed (days/years) to find the item you want, and click again (3 times) to select.
Option 2 is to have a visual calendar. The one you've shown (IMHO) is incomplete. I'd prefer one where the Month and Year values are dropdowns themselves so that you can quickly scan back to 19XX to select a birthday year and/or to jump to say February.
I'd also prefer to have a "Today" button available for the times I'm editing a date and want to "reset" to today.
The added benefit of the visual calendar is that I can easily see what "next Wednesday" or "last Monday" is without having to do any mental calculations (esp. if today is highlighted on the calendar).
The ultimate in my opinion is to have a text field that I can free type into (with validation of course), but with a dropdown visual calendar that I can (if I choose) freely select from.
This all said, the nice feature in a drop down (wherever used) is that you can type the first letter in the focused field to select... so "D" in the month dropdown will auto-select December.